The current landscape of the northeast corner of Illinois was shaped principally by glacial activity, particularly when the Wisconsin glacier began its final stages of melting thousands of years ago. As it receded, it deposited a blanket of unsorted debris, including clay, sand, gravel and boulders, collectively called glacial till. Embedded in the till were large chunks of ice that broke off the melting glacier. As the climate continued to warm, the ice blocks melted, forming depressions which developed into lakes, bogs and marshes.
Volo Bog was originally a deep 50-acre lake, with steep banks and poor drainage. Research on pollen grains preserved in the bog indicates that the lake began filling with vegetation approximately 6,000 years ago. A floating mat, consisting primarily of sphagnum moss formed around the outside edges among the cattails and sedges. As these plants died and decomposed, the peat mat thickened, forming a support material for rooted plants. Because of the lack of drainage and the presence of sphagnum moss, the water in the bog became acidic. This limited the types of plants that could survive and thus created the unique plant communities found in the bog.
Volo Bog is significant in that it exhibits all stages of bog succession. A floating mat of sphagnum moss, cattails and sedges surrounds an open pool of water in the center of the bog. As substrate material thickens, a shrub community dominated by poison sumac and leatherleaf invades the mat. This is eventually replaced by tamarack forest. Surrounding this forest is a second, more extensive shrub zone which abruptly ends and becomes a marsh/sedge meadow community.
Each season brings its own beauty and wonder to Volo Bog and seasonal visits allow for observation of a wide variety of plant and animal life. In the spring, fern fiddleheads reveal their beautiful fronds. Bog buckbean and leatherleaf bloom in abundance. A great variety of songbirds, waterfowl and wading birds stop by as they migrate north to their summer nesting areas.
As spring moves into summer, the orchids appear, including the delicate grass pink and rose pogonia. Great blue and green-backed herons, sandhill cranes, whitetail deer, mink, muskrat, raccoon and many other smaller creatures are often observed. Fall is one of the most dramatic seasons and features the gold of the tamarack needles, the red of poison sumac and the deep green of sphagnum moss. Winter is a good time to identify trees and shrubs by their bark. The bright red berries of the winter berry holly and red leaves of the leatherleaf are a striking contrast to the bright whiteness of the snow-covered ground. Animal tracks in the snow provide evidence of life in the bog - deer, muskrat, weasel and red fox who make their homes in the preserve. Periodically, when seed yield to the north is small, crossbills will visit the bog and can be observed cracking open tamarack cones.
Volo Bog Interpretive Trail: Designed for hikers only, this half-mile interpretive loop leads visitors through each stage of bog succession. It is constructed of wooden dock sections, boardwalks and a woodchip path. Trail brochures, adapted for each season, are available at the visitor center.
Tamarack View Trail: This 2.75-mile trail is designed for hiking and cross-country skiing (with a six-inch minimum snowbase). As park visitors traverse through woods, wetlands, field and prairie, they are given the opportunity to experience and enjoy the diverse communities within the park. From higher elevations along the trail, one can look down into the Volo Bog basin and view the state threatened tamarack trees. The trail begins just south of the visitor center and moves in a counter clockwise direction. All visitors are encouraged to move in the appropriate direction, but it is especially important that skiers do so to avoid accidents. A trail brochure for Tamarack View Trail is also available.
Deerpath Trail and Prairie View Trail: offer an additional 2 miles of hiking through old fields, woods & prairie restoration areas
Volo Bog was first documented by W.G. Waterman of Northwestern Illinois University in 1921. It was originally named the Sayer Bog, after the land's owner, dairy farmer George Sayer. Cyrus Mark, the first director of the Illinois Chapter of the Nature Conservancy, managed a fund-raising campaign that collected $40,000 in donations from school children, groups and individuals for the purchase of the 47.5-acre bog in 1958. The land was deeded to the University of Illinois, which retained ownership until 1970.
In the late 1960s, land developers threatened Volo Bog's survival. Local citizens formed a "Save the Volo Bog" committee and worked to ensure the bog's survival. Dr. William Beecher was instrumental in the campaign, which resulted in the transfer of Volo Bog to the Illinois Department of Natural Resources.
Volo Bog was dedicated as an Illinois Nature Preserve in 1970. Three years later, it was registered as a National Natural Landmark with the United States Department of the Interior. More than 1,100 additional acres of land have been purchased to protect and enlarge the state preserve, which now includes marshes, prairie restoration areas, woodlands and two other bogs.
One of the Illinois Department of Natural Resources' sites with an Interpretive Program Coordinator, Volo Bog offers fun educational programs for people of most ages (4-94+). Naturalist led programs include bog tours, prairie walks, insect and aqua safari's, summer bat programs and more. Assisting the site naturalist, trained volunteers add their skills and experiences at Volo Bog. Volunteer naturalists lead one-hour public tours on Saturdays and Sundays at 11:00 a.m. and 1:00 p.m. Others lead astronomy nights and bird walks. Volunteers also assist with group programs available to school, youth and adult groups. For more details see Interpretive Programs.
Pets are not allowed on the Volo Bog Interpretive Boardwalk Trail due to the sensitive chemistry of the wetland soil. Pets on a 6' leash or shorter are welcome on the other trails at Volo Bog SNA.